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In-Reply-To: <1443153700-15395-3-git-send-email-mikey@neuling.org>
To: Michael Neuling <mikey@neuling.org>, benh@kernel.crashing.org
From: Michael Ellerman <mpe@ellerman.id.au>
Cc: mikey@neuling.org, Aaron Sawdey <sawdey@us.ibm.com>,
 Denis Kirjanov <kda@linux-powerpc.org>, Steve Munroe <sjmunroe@us.ibm.com>,
 linuxppc-dev@ozlabs.org, anton@samba.org
Subject: Re: [v2,
 2/2] powerpc/vdso: Avoid link stack corruption in __get_datapage()
Message-Id: <20151002074709.3AE4F140773@ozlabs.org>
Date: Fri,  2 Oct 2015 17:47:09 +1000 (AEST)
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On Fri, 2015-25-09 at 04:01:40 UTC, Michael Neuling wrote:
> powerpc has a link register (lr) used for calling functions. We "bl
> <func>" to call a function, and "blr" to return back to the call site.

<snip, geez that was long>

> For the benchmark in tools/testing/selftests/powerpc/benchmarks/gettimeofday.c
>   POWER8:
>     64bit gets ~4% improvement
>     32bit gets ~9% improvement
>   POWER7:
>     64bit gets ~7% improvement
> 
> Signed-off-by: Michael Neuling <mikey@neuling.org>
> Reported-by: Aaron Sawdey <sawdey@us.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/c974809a26a13e40254dbe3c

cheers